Driving mandrel for rolls of paper in printing and similar machines



Jan. 30, 1962 K. s. A. SKALLQUIST 3,013,977

DRIVING MANDREL FOR ROLLS OF PAPER IN PRINTING AND SIMILAR MACHINESFiled Aug. 24, 1959 2 Sheets-Sheet 1 I I 2 8 /V 41 Mg ,0 y'- d II/ "-2Jan. 30, 1962 K. s. A. SKAL UIST 3,018,977 DRIVING MAND FOR ROLLS P P RIN PRINTING SIMILAR MACHI Filed Aug. 24, 1959 2 Sheets-Sheet 2 iteStates 3,018,977 DRIVING MANDREL FOR ROLLS OF PAPER IN PRINTING ANDSIMILAR MACHINES Karl Sture Alvar Skallquist, Alvsjo, Sweden, assignorto Dagens Nyheters Aktiebolag, Stockholm, Sweden, a

corporation of Sweden Filed Aug. 24, 1959, Ser. No. 835,729 Claimspriority, application Sweden Aug. 27, 1958 3 Claims. (Cl. 242-72) ,forethe automatic connection of the mandrel to the roll should be such thatit can prevent relative rotation in either sense between the roll andthe mandrel.

A paper printing machine according to this invention comprises a spindleadapted to receive a roll of material and to be driven by a powersource; gripping members movably mounted on the spindle and adapted tobe moved into firm engagement with the roll to connect the roll to thespindle upon movement of the spindle relatively to the roll caused byinertia of the roll upon starting to rotate; a locking device movable inrelation to the spindle and adapted to retainthe gripping members in acertain position relative to the spindle; and a ratchet means by whichsaid locking device is connected to said spindle and which is such as topermit relative movement between the locking device and spindle in adirection to permit the gripping members to move into firm engagementwith the roll but which prevents such relative movement in the oppositedirection.

Thus mere mounting of the roll upon the spindle will, when the spindlestarts to rotate, result in connection of the roll to the spindle. Inaddition the grip ping members are held by the locking device in contactwith the roll when the spindle is braked.

It is also desirable to be able'to remove rapidly the bobbin of an emptyroll. This involves disengagement of the gripping members from the roll.

According to a further feature of this invention, the ratchet parts areseparated, by axial movement of the bobbin of the empty roll, and thispermits the locking device to move relatively to the spindle to permitthe automatic disengagement of the gripping members by radial resiliencyof the bobbin of the empty roll.

FIG. 1 is a partially sectional side view of a spindle along the lineI--I in FIG. 3, FIG. 2 an end view of the spindle in the direction ofthe arrow A in FIGURE 1,

FIG. 3 a cross-sectional view along the line III-4H in FIG. 1, and FIG.4 a longitudinal sectional view along the line IVIV in FIG. 2 FIGS. 5and 6 are illustrative of the mode of operation of a detail, and FIG. 7is a view of the mandrel on which a roll of paper is mounted.

' Referring first to FIG. 7, referenceletter A'denotes a atent icespindle which is connected to a shart 40 which is mounted for rotationin a frame 41 by means of a ball bearing 42. Mounted on the spindle A isa roll of paper B which is wound up on a bobbin 30 which may consist oftightly wound paper. The bobbin 30 has a certain inherent radialresiliency, as is well known in the art. The shaft 40 is suitably drivenby a motor, not shown, and may be combined with a braking mechanism, notshown, such as a friction brake of conventional type.

As will be seen from FIG. 4 which shows a longitudinal section of thespindle A from the axis of rotation to the periphery, the spindlecomprises a core 1 which has a conical portion 1a to be connected to theshaft 40 which may be driven by an electric motor, not shown. The corehas a central bore 2 for a locking screw which can be screwed into thedriving shaft 40. The core further has a plurality of substantiallyaxial grooves 3. Each groove has a rounded bottom 4 (FIG. 3) and sidewalls 5 and 6 which make an angle with each other as viewed incrosssection. The grooves receive pivotally mounted gripping members 7for the roll of paper. Each gripping member is rounded at its inner endin accordance with the shape of the bottom 4 of the groove 3. At itsradially inner end, each gripping member, as shown in FIG. 4, hasjournals 8 one of which enters a bore 9 in the core 1, whereas the otherone enters a bore 10 in a front ring 11 which is bolted to the core bymeans of screws 12, FIG. 2, and also serves to limit axial movement ofthe gripping members along the grooves 3.

The grooved portion 111 of the core 1 is surrounded by a sleeve 15 whichi slightly conically tapering outwardly and formed with axial aperturesor slots 16 through which the tongue-like clamping portions of thegripping members 7 extend outwardly. The sleeve 15 is mounted forturning movement as well as axial displacement relatively to the portion1b of the core 1. Longitudinally, the gripping members snugly fit theslots 16 so that they will be axially displaced together with the drum.

The sleeve 15 is connectible to the core by a ratchet comprising lockingteeth 17 which are arranged in a closed circle and extend axially on aflange 18. The locking teeth 17 are engaged by locking members or dogs20 provided in the core 1 or, as illustrated, in a separate ring 21which by means of screws 22 is secured to the core. The locking dogs areaxially displaceably mounted in bores 23 and biased by compressionsprings 24. Each locking dog has a flange 25 adapted to abut against ashoulder in the ring '21 for limitation of the outward movement of thedogs. The flange 25 is guided in the ring '21 such as to prevent the dogfrom turning in its bore. A suitable number of locking dogs 29 arecircumferentially spaced apart.

In the position illustrated, the ratchet means 17, 20 is engaged. At thestart when a new roll of paper is to be mounted on .the spindle, thesleeve 15 and the gripping members 7 are in their left hand endpositions and the dogs 20 are not in engagement with teeth 17. In thisposition, the gripping members 7 assume the extreme slanting positionswith respect to the radial position, as shown in FIGS. 3 and 5, wherethe outer ends of the gripping members but slightly project from theouter surface of the sleeve 15, but nevertheles areable to engage thewallof the central bore of the bobbin of aroll of paper which is slidonto the spindle. As the roll of paper is slid onto the sleeve 15, thesleeve will be moved to the right as viewed in FIG. 4 and the teeth 20engage the ring 17. When at the same time or thereafter the core 1 isrotated by the shaft 40 in the direction of the arrow p, FIG. 5, thegripping members 7, due to the relative movement between the core andthe roll which lags because of its inertia, is pivoted in the coretowards its dead center position and gradually increase the hold of thebobbin 3i of the roll until the core 1 and the roll 13 are firmlyconnected with each other; this movement is permitted by the ratchet,the dogs sliding over the oblique faces of the teeth 17. Finally, theroll is locked to the spindle A in one direction by the gripping members7 and in the other direction by the sleeve 15 which is prevented fromturning on the core by the ratchet 17, 20, the sleeve thus constitutinga locking device for the gripping members.

After the roll of paper has been speeded up to the required velocity andthe paper sheet has assumed its operative position in the printingmachine, a braking action may be applied through the driving shaft 40 tothe spindle A. The braking force is transmitted to the roll by thegripping members 7, which are prevented from pivoting from the positionof FIGURE 6 to the position of FIGURE by the sleeve; the sleeve is nowprevented from turning on the core by the ratchet 17, 20.

The mode of operation of the gripping elements 7 is diagrammaticallyillustrated in FIGS. 5 and 6. FIG. 5 shows a gripping member in theposition which it assumes when a roll of paper B is slid onto thespindle. When the spindle 1 rotates in the direction of the arrow p, thegripping members gradually increase their hold of the bobbin until theposition shown in FIG. 6 is obtained in which the pants are firmlyconnected to each other. This clamping position is usually obtained veryquickly, say after a turning movement of a few degrees. The centrallongitudinal plane 31, FIG. 6, of the gripping members is always locatedlateral of and on the same side of the axis 32 of the spindle so that,in operation, the gripping members do not reach the dead centerposition. In FIG. 2, the gripping members are shown in extreme positionswhich never occur in practical operation.

After the paper has been wound oif, the bobbin 30 has to be removed fromthe spindle to give way for a new roll of paper. When the bobbin isdrawn oif it imparts a short axial movement to the gripping members andthe sleeve 15, resulting in that the locking teeth 17 are disengagedfrom the dogs 20. Consequently, the sleeve can turn freely relative tothe core 1 of the spindle, and also the gripping members are free topivot in their slots. Due to its inherent radial resiliency, the bobbin30 exerts a pressure on the gripping members 7 in the direction of thearrow p FIG. 6. This pressure causes a relative turning movement of theparts 1 and 15, 80 due to which the gripping members are moved back tothe position shown in FIG. 5 and loosen their firm hold on the bobbin 30which then can be easily drawn ofi the spindle.

Due to the arrangement described, a roll of paper can be automaticallylocked to a driving spindle in both directions of rotation, and thelocking engagement can be readily released by a simple axial movement ofthe roll to be exchanged. As a result, the necessary operations areconsiderably simplified as compared with conventional arrangements.

It should be possible to engage the members 17 and 20 in shortcircumferential steps so as to ensure fine adjustment of the lockingmovement without any play. Nevertheless very strong locking teeth may beused if the circumferential spacing of the locking dogs or of groups oflocking dogs is other than the circular pitch of the locking teeth. Byway of example, sixty-three teeth 17 may be provided and six lockingteeth may be equally circumferentially spaced apart. In this case agroup of dogs will be active upon turning of the toothed member througha distance equal to half the circular pitch of the teeth.

What I claim is:

1. In a printing machine, a drive mandrel comprising a spindle, saidspindle comprising a core adapted to be driven by a power source and asleeve axially slidable and turnably mounted on said core and having anumber of apertures, said sleeve being such that it is adapted to enterthe bore of a roll of material; gripping members pivotally mounted ingrooves in said core to project through said apertures in said sleeveand adapted to be pivoted towards their dead center position into firmengagement with said roll to connect said roll to said core by relativemovement of said spindle relatively to said roll caused by'inertia' ofsaid roll upon starting to rotate; and a ratchet which comprisesa ringof teeth on said sleeve and at least one dog on said core arranged topermit said sleeveto turn relatively to said core in one direction toenable'said gripping members to engage said roll and to prevent saidsleeve from turning relatively to said core in the opposite directionwhereby the edges of said apertures in said sleeve engage said membersto prevent them moving out of firm engagement with said roll, andmounting of said roll on saidsleeve slides said sleeve on said core inoneaxial direction to move said ring into engagement with said dogandremoval of said roll slides said sleeve in the opposite axialdirection to'move said ring out of engagement with said dog, so thatsaid roll, by virtue of its radial resilience, is thereupon able to movesaid gripping members out of firm engagement with its bore.

2. In a printing'machine, a drive mandrel comprising a spindle, saidspindle comprising a core adapted to be driven by a power source and asleeve axially and turnably slidably mounted on said core and having anumber of apertures, said sleeve being'adapted to enter the bore of aroll of material; gripping members in the form of longitudinallyextending plates whose radial inner ends are pivotally mounted andaxially displaceable in axial grooves in said'core and which extendthrough axial apertures in said sleeve, said members being closelysurrounded by the edges of said apertures and pivotable towards theirdead centerposition into firm engagement with the bore of said roll toconnect said roll to said core by relative movement of said spindlerelatively to said roll caused by inertia of said roll upon starting torotate; and a. ratchet arranged to permit said sleeve to turn relativelyto said core in one direction to enable said gripping members to engagesaid roll and which prevents said sleeve from turning relatively to saidcore in the opposite direction whereby the edges of said apertures insaid Sleeve engage said members to prevent them moving out of firmengagement with said roll, said ratchet comprising a toothed ring onsaid sleeve and a plurality of spring biased dogs on said core wherebymounting of said roll on said sleeve slides said gripping members andsaid sleeve in one axial direction on said core to move said ring intoengagement with said dogs and removal of said roll slides said grippingmembers in their grooves and said sleeve in the opposite axial directionto move said ring out of engagement with said dogs so that said roll, byvirtue of its radial resilience, is thereupon able to pivot saidgripping members out of firm engagement with its bore.

3. In a printing machine, a mandrel for a roll of material comprising arotatably mounted core tapering at its free end and a sleeve turnablymounted on said core and having a number of apertures, said sleeve beingsuch that it is adapted to enter the bore of the roll; gripping memberspivotally mounted in grooves in said core to project through saidapertures in said sleeve and adapted to be pivoted towards their deadcentre position into firm engagement with said roll to connect said rollto said core by turning movement of said sleeve relatively to said core;said sleeve being slidable on said core in axial directions thereof; anda ratchet which comprises a ring of teeth on said sleeve and at leastone dog on said core arranged to permit said sleeve to turn relativelyto said core in one direction to enable said gripping members to engagesaid roll and to prevent said sleeve from turning relatively to saidcore in the opposite direction whereby the edges of said apertures insaid sleeve engage said members to prevent them from moving out of firmengagement with said roll, and mouting of said roll on said sleeveslides said sleeve on said core in one axial direction to move said ringinto engagement with said dog, and removal of said roll slides saidsleeve in the opposite axial direction to move said ring out ofengagement with said dog.

References Cited in the file of this patent UNITED STATES PATENTS1,188,369 Chernack June 20, 1916 1,858,607 Whalen May 17, 1932 FOREIGNPATENTS 530,480 Great Britain Dec. 12, 1940 I 139,151 Sweden Feb. 17,1953

